T-Mobile CEO Mike Katz is leaving after 28 years, as the carrier shakes up top ranks and taps former AT&T leader

T-Mobile’s longest-running Un-carrier developer recently turned to Un-carriers himself.

Mike Katz, who started selling VoiceStream phones in Circuit City 28 years ago and rose to help T-Mobile go from being a competitor to the biggest competitor in the wireless industry, is leaving the Bellevue, Wash.-based carrier. as part of a broader executive shake-up under CEO Srini Gopalan, who took over in November.

Katz, T-Mobile’s chief business and product officer, is leaving to pursue a “new professional interest,” the company said in a press release and SEC filing. The company did not provide details. We contacted Katz to find out more about his plans.

He will remain as a strategic advisor until December 2026.

His works are divided into three categories:

• Chris Sambar, a wireless industry veteran who spent two decades at rival AT&T and most recently served as COO of Public Storage, will join as chief operating officer before Oct. 14, which oversees T-Mobile’s SMB, businesses and government businesses.
• André Almeida steps into an expanded role as chief marketing officer, product and broadband.
• CTO John Saw’s purview will expand to include product engineering and cybersecurity.

Katz was appointed last month to the newly formed Economic Development Council of Gov. Bob Ferguson, a 26-member panel of business, labor and tribal leaders. His position on the council following his departure from T-Mobile is unclear.

In his career at T-Mobile, Katz led the company’s business team, where he helped triple the number of customers, and later oversaw marketing, strategy and products, shaping some of the carrier’s most visible initiatives: T-Mobile Tuesdays, Magenta Status, and more.

“We built a regional player into a national powerhouse, turned the industry on its head with the Un-Carrier movement, pulled off the Sprint merger, and got into the broadband business,” Katz said in a LinkedIn post announcing his departure.

Gopalan praised Katz in a press release, calling him “the driving force behind many of the initiatives that have transformed our company and our industry.”

Sambar’s hiring is a significant move for T-Mobile, which is building its Un-carrier brand in part by positioning itself as a differentiator than industry giants AT&T and Verizon. At AT&T, Sambar led the design of the company’s 5G mobile network and oversaw the construction and deployment of FirstNet, a national public safety communications network.

A graduate of the US Naval Academy who served more than 20 years in the Navy, Sambar will report directly to Gopalan and lead T-Mobile’s push into business, government, and emerging growth areas including T-Ads and virtual AI.